-LRB- CNN -RRB- -- A cargo train derailed and crashed into homes Sunday in a sprawling Kenyan slum , the Red Cross said .

Rescue efforts are under way to free residents trapped in damaged homes in the capital city of Nairobi , the agency said .

At least five people were transported to a local hospital , Red Cross said on its Twitter page .

Kibera -- one of Africa 's largest slums -- is filled with rows of homes made from a mixture of mud , tin , wood and concrete . A railway passes through the neighborhood .

The settlement is home to hundreds of thousands .

CNN 's Christabelle Fombu contributed to this report

@highlight

NEW : At least five people are taken to a local hospital

@highlight

NEW : Rescue efforts are under way to free trapped residents

@highlight

Kibera is one of Africa 's largest slums

@highlight

A railway passes through the neighborhood